C++ BLOB_CHOICE::min_xheight方法代码示例

// Returns true if *this and other agree on the baseline and x-height
// to within some tolerance based on a given estimate of the x-height.
bool BLOB_CHOICE::PosAndSizeAgree(const BLOB_CHOICE& other, float x_height,
                                  bool debug) const {
  double baseline_diff = fabs(yshift() - other.yshift());
  if (baseline_diff > kMaxBaselineDrift * x_height) {
    if (debug) {
      tprintf("Baseline diff %g for %d v %d\n",
              baseline_diff, unichar_id_, other.unichar_id_);
    }
    return false;
  }
  double this_range = max_xheight() - min_xheight();
  double other_range = other.max_xheight() - other.min_xheight();
  double denominator = ClipToRange(MIN(this_range, other_range),
                                   1.0, kMaxOverlapDenominator * x_height);
  double overlap = MIN(max_xheight(), other.max_xheight()) -
                   MAX(min_xheight(), other.min_xheight());
  overlap /= denominator;
  if (debug) {
    tprintf("PosAndSize for %d v %d: bl diff = %g, ranges %g, %g / %g ->%g\n",
            unichar_id_, other.unichar_id_, baseline_diff,
            this_range, other_range, denominator, overlap);
  }

  return overlap >= kMinXHeightMatch;
}

// Creates a fake blob choice from the combination of the given fragments.
// unichar is the class to be made from the combination,
// expanded_fragment_lengths[choice_index] is the number of fragments to use.
// old_choices[choice_index] has the classifier output for each fragment.
// choice index initially indexes the last fragment and should be decremented
// expanded_fragment_lengths[choice_index] times to get the earlier fragments.
// Guarantees to return something non-null, or abort!
BLOB_CHOICE* Wordrec::rebuild_fragments(
    const char* unichar,
    const char* expanded_fragment_lengths,
    int choice_index,
    BLOB_CHOICE_LIST_VECTOR *old_choices) {
  float rating = 0.0f;
  float certainty = 0.0f;
  inT16 min_xheight = -MAX_INT16;
  inT16 max_xheight = MAX_INT16;
  for (int fragment_pieces = expanded_fragment_lengths[choice_index] - 1;
       fragment_pieces >= 0; --fragment_pieces, --choice_index) {
    // Get a pointer to the classifier results from the old_choices.
    BLOB_CHOICE_LIST *current_choices = old_choices->get(choice_index);
    // Populate fragment with updated values and look for the
    // fragment with the same values in current_choices.
    // Update rating and certainty of the character being composed.
    CHAR_FRAGMENT fragment;
    fragment.set_all(unichar, fragment_pieces,
                     expanded_fragment_lengths[choice_index], false);
    BLOB_CHOICE_IT choice_it(current_choices);
    for (choice_it.mark_cycle_pt(); !choice_it.cycled_list();
        choice_it.forward()) {
      BLOB_CHOICE* choice = choice_it.data();
      const CHAR_FRAGMENT *current_fragment =
          getDict().getUnicharset().get_fragment(choice->unichar_id());
      if (current_fragment && fragment.equals(current_fragment)) {
        rating += choice->rating();
        if (choice->certainty() < certainty) {
          certainty = choice->certainty();
        }
        IntersectRange(choice->min_xheight(), choice->max_xheight(),
                       &min_xheight, &max_xheight);
        break;
      }
    }
    if (choice_it.cycled_list()) {
      print_ratings_list("Failure", current_choices, unicharset);
      tprintf("Failed to find fragment %s at index=%d\n",
              fragment.to_string().string(), choice_index);
    }
    ASSERT_HOST(!choice_it.cycled_list());  // Be sure we found the fragment.
  }
  return new BLOB_CHOICE(getDict().getUnicharset().unichar_to_id(unichar),
                         rating, certainty, -1, -1, 0,
                         min_xheight, max_xheight, false);
}